6420490 has 8 divisors (see below), whose sum is σ = 11556900. Its totient is φ = 2568192.

The previous prime is 6420487. The next prime is 6420511. The reversal of 6420490 is 940246.

It can be written as a sum of positive squares in 2 ways, for example, as 6395841 + 24649 = 2529^2 + 157^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 321015 + ... + 321034.

Almost surely, 2^6420490 is an apocalyptic number.

6420490 is a deficient number, since it is larger than the sum of its proper divisors (5136410).

6420490 is a wasteful number, since it uses less digits than its factorization.

6420490 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 642056.

The product of its (nonzero) digits is 1728, while the sum is 25.

The square root of 6420490 is about 2533.8685838062. The cubic root of 6420490 is about 185.8614800929.

The spelling of 6420490 in words is "six million, four hundred twenty thousand, four hundred ninety".